Hello, this has me scratching my head. 05 f150 club cab. I’m trying to get the ac working. Hot air in both lines even after I’ve had it vacuumed completely after it runs somehow it builds up pressure in there there’s a leak anyways if that wasn’t enough, I come out to Truck that clicks but won’t start the gauges, flutter flicker and now I have a buzzing motor sound. I thought was the fuel pump in between the bed and the cab underneath somewhere I cannot find this noise anywhere. Feels like it’s up inside the frame, but it only comes on when the key is out of the ignition. It shuts off when you turn the ignition on.